Allied Telesis AT-S62 - Manual (Page 278)

Chapter 16: Quality of Service
Section II: Advanced Operations 278
If the amount of traffic flow matches the maximum bandwidth, no
traffic is dropped because the number of tokens added to the
bucket matches the number being used by the traffic. However,
no unused tokens will accumulate in the bucket. If the traffic
increases, the excess traffic will be discarded since no tokens are
available for handling the increase.
If the traffic is below the maximum bandwidth, unused tokens will
accumulate in the bucket since the actual bandwidth falls below
the specified maximum. The unused tokens will be available for
handling excess traffic should the traffic exceed the maximum
bandwidth. Should an increase in traffic continue to the point
where all the unused tokens are used up, packets will be
discarded.
Unused tokens accumulate in the bucket until the bucket reaches
maximum capacity, set by this parameter. Once the maximum
capacity of the bucket is reached, no extra tokens are added.
Note
To use this parameter you must specify a maximum bandwidth
using Option 6 - Max Bandwidth. Specifying a token bucket size
without also specifying a maximum bandwidth serves no function.
8 - Priority
Specifies the priority value in the IEEE 802.1p tag control field that
traffic belonging to this traffic class is assigned. Priority values
range from 0 to 7 with 0 being the lowest priority and 7 being the
highest priority. Incoming frames are mapped into one of four
Class of Service (CoS) queues based on the priority value.
If you want the packets to retain the new value when they exit the
switch, change option 9, Remark Priority, to Yes.
If you specify a new user priority value here and in Flow Group, the
value in Flow Group overwrites the value here.
9 - Remark Priority
Replaces the user priority value in the packets with the new value
specified in option 4, Priority, if set to Yes. If set to No, which is the
default, the packets retain their preexisting priority level when
they leave the switch.
A - Flow Group List
Specifies the flow groups to be assigned to the traffic class. The
specified flow groups must already exist. Separate multiple IDs
with commas (e.g., 4,11,13).
6. After configuring the parameters, type C to select Create Traffic Class.